Process of purifying water



(No Model.)

"TE W. DUFFY. ESS OF PURIPYING WATER.

No. 314,003. Patented Mar. 17, 1885.

INVENTUR N. PETERS, Pnxn-Lnhagrulwr. Washington. DJ;

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Unir-sn Santas PATENT Ormea..

THOMAS WILLIAM DUFFY, OF MEDFORD, MASSACHUSETTS, ASSIGNOR, BY

l DIRECT AND MESNE ASSIGNMENTS, TO THE WAINWRIGHT MANUFAC- TUBING COMPANY, OF PORTLAND, MAINE.

PROCESS OF PURIFYING WATER.

SPECIFICATION forming part of Letters Patent N o. 314,003, dated March 17, 1885.

(No model.)

To ali-whom it 11mg concern.-

Be it known that I, THOMAS WILLIAM DUF- FY, of Medford, in the county of Middlesex and State of Massachusetts, a subject of her Majesty Queen Victoria, have invented a new and useful Improvement in the Art of `Purifying Water, of which the following is a full, clear, and exact description; reference being had to the accompanying drawings, making a part hereof. l y

The purpose of my invention is to rid water containing carbonates of lime and magnesia of those impurities in such a way that it may be used in boilers without injury. The main requirement of such a process is that the carbonic-acid gas, which the water so often holds` in solution, together with that thrown oft by the earbonates while they are becoming insoluble under heat, shall be allowed to escape, 2o so that the gas cannot redissolve the; carbonates before the water cools suiiieiently and the earbonates are separated from it. It is necessary that during the process the water shall not be allowed to absorb any other deleterious matter.

' My 'mprovement consists, chielly, in, iirst, vheating the water to a temperature sufficient to precipitate the carbonatos; second, allowing the carbonio-acid gas to escape from the water so heated; third, separating the solids which have been precipitated from ythe w ter, the

Water at all times being so confined that it cannot mix with or absorb any new impurities.

The apparatus necessary for the putting of my process into operation is, first, a heater of some sort with means for heating water to the proper temperature, with an inlet arid outlet for the water and an outlet for the carbonicaeid gas; second, suitable means for separating 4o the solids in the water from the water--as, for

example, a iilter; third, means for keeping up a proper circulation of water through the apparatus. These means maybe contained in one machine; but I prefer, for convenience, to

separate them, and have shown in the drawings an apparatus which I believe to be most convenient for the purpose, a portion of it being of my own invention, and the subject of application for Letters Patent No. 119, 535.

Figure 1 is a vertical section of the appara- 5o tus; Fig. 2, ahorizontal section of the heater, and Fig. 3 a plan view of the agitator.

A is a feed-water heater, provided with a water-inlet, a, near the top, and a water-outlet, a', near the bottom. It is also provided 55 with concentric annular chambers B, formed by the concentric cylinders b, for holding the steam, by means ot' which the water is to be heated. These chambers are closed at one end with the cross-pipe b', and at the other. 6o with the cross-pipe b2, the steam-inlet b and outlet b4 connecting with these cross-pi pes, as shown.

C is an agitator consisting of a number oi' blades or arms which are attached to a sleeve, 6 5 c, about the steam outlet 6*, and passing through a stulng-box, c', at the bottom ofthe heater. This sleeve and agitator are rotated by means of power applied through the gearing c'l ci. 7o

D is a vent-pipe for leading off the steam and carbonio-acid gaswhich are thrown ofi from the water. This pipe carries the steam and gas through the water, its mouth being above the level of the water in the heater. 7 5 This steam and gas maybe further utilized for the purposes of heating, if thought desirable.

Water containing carbonates generally con tains sulphates aswell, which, however, will only precipitate when the temperature is above 8o 212 Fahrenheit; hence it is best that the heater should be capable ot heating Water to the necessary degree above 212. NVhen such a course is desirable, the vent-pipe D (which is not shown in section 'in the drawings) should 85 have a smallinternal diameter, so as to let the steam and gas blow oft` without so reducing the p'ressure in the heater as to prevent the raising of the temperature to a suiiiciently high degree to precipitate the sulphates. The 9o internal diameter of this vent in any case must depend upon the heating-surface of the heater used. The larger the heatingsurfaceth`e larger the vent may be.

l l E is adoubieacting pump fory the purposes of maintaining a constant water-level,

' vIO which shall allow room in the heater for the collection of gas and steam, and also prevent any overiiow of Water through the pipe D.

F is a filter of suitable construction,through which lthe Water is forced from the heater. The suction-pipe G leads from the reservoir or source of supply to the pump, and from thence into the heater at a, and the pipe G from the heater at a to the pump and filter. Gr2 leads from the filter to the boiler. A pipe, G3, provided with a cock is shown joining the pipe bB and the pipe G2. Under ordinary circumstances the cock in this pipe G is closed and the pipe not used. When it is desired to blow steam threugh the filter for the purpose of cleaning it out,this cock is opened, and the cocks in the pipe b3 and G2 are closed, so that the steam will pass the pipe b3 and into the farther side of the filter, through a portion of the pipe G2, and out through the cock G* in the chamber on the right of the filter, which has been opened for the purpose.

My process as carried out with this apparatus is as follows: Water is pumped into the heater through the inlet c', and is heated by means of steam or its equivalent circulated through the chambers B. When heated to a sufficient degree, the carbonates in solution vwill precipitate, throwing off carbonic-aeid gas. The Water also will throw off any carbonic-acid gas held in solution, and this gas and any steam which may be formed will pass off from the chamber above the Water-level through the pipe D. The Water, being thus rid of all carbonio-acid gas, cannot redissolve the precipitated carbonates. The agitator C, being rotated, will keep the water in motion and prevent any impurities from settling on any part ofthe heater. As the pump will maintain a constant water-lcvel in the heater, and as the stef'qm and gas will collect above the Waterdeveljwith greater rapidity, owing to the large heating-surface, than it can escape through the vent, such being the proportion of heating-surface to the vent in the apparatus, pressure Will accumulate in the heater sufficient to enable the temperature of the feed-water to be raised to a high enough degree to cause any sulphates held in solution to precipitate as Well as the carbonatcs. The

water will be drawn off into the boiler or other reservoir through the filter F at a proper temperature and the solid matter separated from it. The water should be circulated slowly, so as to give the gas sufficient opportunity to escape. I preferlto draw off the heated water der that the steam may not escape with too great rapidity, and so reduce the pressure in the heater as to prevent the Water from being heated above 212 Fahrenheit and prevent the sulphates from being precipitated. By means ot'a cock attached to the pipe D the escape through the pipe D can be regulated at pleasure, so as to retain the pressure in the heater necessary to precipitate the sulphates and yet take oft the gas, the amountof pressure in the heater being indicated by a gage attached thereto above the water-level. This cock and gage are not shown in the drawings, nor are they necessary parts of the apparatus.

What I claim as my invention is- 1. The process above described of freeing water from carbonates of linie and magnesia insoluble at a high temperature, which consists in heating the water to a temperature sufficient to precipitate the carbonates held in solution` then freeing it from carbonic-acid gas, and then separating from it the insoluble matter, all as set forth.

2. The process above described of freeing water from salts of lime and maguesia insoluble at a high temperature, which consists in heating the water under pressure to a temperature sufficient to precipitate the salts held in solution, at the same time freeing it from carbonic-aeid gas and stean1,then separating from it the insoluble matter While still at a high pressure and temperature, all as set forth.

3. The process above described of freeing Water from salts of lime and magnesia which are insoluble at high temperature, consisting in heating the Water under pressure to a temperature sufficient to render said salts insoluble, agitating the water whileit is being heated and freeing the water from carbonio-acid gas, and then separating the insoluble particles from the Water While it is still at high temperature and pressure, alias set forth.

In testimony whereof I have hereunto subscribed my name this 14th day ol' November, A. D. 1883.

THOMAS VILLIAM DUFFY.

Witnesses:

J. HENRY TAYLOR, GEORGE O. G. Colima. 

